Cellulosic composition of matter containing trimethylene glycol



Dec. 15, 1931. RRQLL ON OF MATTER CONTAINING TRIMETHYLENE GLYCOL DIBUTYRATE Filed Aug. 30, 1929 6.3 E iiiznln 243F252 n25 A 0 0 0 w w b 5 0 0 J I 0 I 2 M 0 0 0 0 0 n 0 0 0 M 5 2 m Jwoentoc Sim/5P1 LI- Dfirr all Patented Dec. 15, 1931 UNITED s'rA ras PATENT our-10E STEWART J. OARROLQ, OF ROCHESTER, NEW YORK, ASSIGNO'R TO KODAK (DIIPAN'Y; OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK CELLULOSIC COMEPOSITION OF MATTER CONTAININGT'RIMETBYLENE GL'YCOL I DIBUTYRATE Application filed August 30, 1929. Serial No. 889,460.

This invention relates to compositions of matter in which cellulose derivatives, such as cellulose acetate, cellulose nitrate or cellulose ether, are combined or mixed with other substances, such as a compatible plasticizer, and a common solvent for both, with or without other useful addition agents, so that the re sulting product will have properties such as will make the composition highly advantageous for use in the plastic and analogous arts, such, for instance, as the manufacture of wrapping sheets, photographic film, artificial silk, varnishes or lacquers, and the like.

Oneob ject of this invention is to produce a composition of matter which may be made into permanently transparent, strong and flexible sheets or films of desired thinness which are substantially water roof, are unaffected by ordinary photographic fluids and possess the desired properties of a support for sensitive photographic coatings. Another object of my invention is to produce a composition which is capable of easy and convenient manipulation in the plastic and anal- 2 ogous arts, such as in the manufacture of sheets, films, artificial silk. filaments, varnishes, lacquers and the like; and to produce a composition which will not injure, or be injured by, the substances or surfaces with which it is associated during manufacture,

storage or use. Other and further objects will hereinafter become apparent to those skilled in the art to which this invention pertains.

While cellulose acetates, nitrates and ethers have been known for decades it has also been known that to utilize them in the various plastic arts it. is necessary to mix therewith such plasticizing or conditioning agents as camphor, castor oil, triphenyl phosphate, monochlornaphthalene or the like. Certain of these and. other addition agents are also added for the purpose of reducing the inflammability of the product. Plastic inducing agents, such as the higher alcohols and their esters, are sometimes also added. Similarly addition compounds of various kinds have been employed to increase flexibility, transparency, toughness and other proper- 50 ties whiciiqiirill enhance the value of the resulting product. Addition products for the same or similar purposes are also added to cellulose acetates, nitrates and ethers to prepare them for use in the other plastic arts, such as in the manufacture of lacquers, varnishes, artificial silk filaments, moulded compounds and the like. While the plasticizers or other addition agents heretofore discovered have had their utility in the art, the increasing use to which cellulose derivatives have been put and the increasing number of desirable properties required of the cellulose derivative for most purposes has made the discovery of new and economical plasticizers or other addition agents a matter of considerable importance to the art.

I have discovered that valuable properties may be induced .in and/or contributed to compositions containing cellulose derivatives, such as cellulose acetate, by adding thereto the plasticizing compound trimethylene glycol dibutyrate in the presence of a solvent, such as acetone, which will dissolve both the cellulose derivative and plasticizer. This plasticizer has a boiling point of 125 to 130 C. at 8 millimeters pressure and has the structural formula of It is oompatible with cellulose derivatives and particularly compatible with cellulose acetate in the percentages hereinafter given. It is not an expensive compound and not particularly difficult to produce, or obtain upon the open market. The particularly useful properties which it induces in or contributes to a cellulosic composition containing it are hereinafter enumerated.

In order that those skilled in this art .may

better understand my inventidn I would state, by way of illustration, that for the manufacture of photographic'film or other sheets my new composition ofmatter may be compounded as follows: parts of acetone soluble cellulose acetate .i. e. cellulose acetate containing from 36% to 42% acetyl radical, approximately, is dissolved with stirring at atmospheric temperature 300 to 500 parts, preferably 400 parts, by weight, of acetone.

To this. solution may be added from 10 to arts by weight, of trimethylene glycol diutyrate, it being found preferable to employ approximately 30 parts thereof. Within the limits stated, the amount of plasticizer may be decreased or increased, depending upon whether it is desired to decrease or increase, respectively, the properties which this plasticizer contributes to the finished product. The amount of solvent employed may also be decreased or increased, depending upon whether it is desired to have a more or less freely flowing composition, respectively.

A composition of matter prepared as above described may be deposited upon any suitable film forming surface to form a film or sheet, as is well known to those skilled in the art.

,A film so produced has permanently brilliant transparency and low infiammability, burnmg no more readily than ordinary newsprint.

Such film is exceptionally tough and flexible as shownby the fact that .it will withstand many folds upon a modified Schopper foldtester (commonly used for such purposes) without breaking and that even after being subjected as high as for 177 days to air maintained at a temperature of 65 C. the film still maintains flexibility, demonstrating that the film will withstand ordinary usage satisfactorily for many years, whereas a fihn formed from a mere solution of celluloseacetate in acetone or other similar solvent is brittle and fragile after being subjected to the same treatment for as little as thirty days or even a lesser time. The sum total of the above advantageous properties of a product produced from my new composition is considerably in excess of that of products produced with what have previously been regarded as the better plasticizers.

Other similar solvents (instead of acetone) which are compatible with the cellulose acetate and my new plasticizer may also occur to those skilled in this art. In like manner this plasticizer may be compound with other single organic esters of cellulose, such as cellulose propionate, butyrate and the like, or with mixed organic and/or inorganic esters, such as cellulose aceto-stearate, aceto-malate, or cellulose nitro-acetate, or with the cellulose ethers, a suitable solvent which will dissolve both the cellulosic derivative and the pasticizer being employed.

The accompanying drawing, forming a.

part of this application, clearly illustrates the particular advantages of. employing my novel plasticizer in the plastic arts. In this drawing there are plotted lines or curves graphically depicting the properties of film produced from a composition containing cellulose acetate and this plasticizer. On the horizontal axis isindicated the various percentages of my plasticizer that may be employed with the cellulosic derivative, this percentage being given in parts added to the that the film will maintain flexibility when subjected to air kept'at a temperature of C. The curve (A) depicts initial flexibility of the film and the curve (B) depicts the ability of the filmto maintain flexibilityall with various percentages of my novel plasticizer andiall as compared to the respective pro erties of a film produced from a solution 0 cellulose acetate in acetone and a hypothetical inert material substituted for the plasticizer as denoted by curve (D) indi cating unity of 100% and 30 days for (a) and (b) It will thus be noted that my novel plastlcizer has the faculty of giving, to a product produced therefrom, exceptionally good initial flexibility and that the product maintains its flexibility exceedingly well.

The preferred percentage of my plasticizer which it is desirable to employ to contribute any particular property to the final product will be obvious from an inspection of this drawing; the best percentage to employ will depend upon which roperty it is desired to feature most in the al product.

In as much as my above described composition of matter is quite useful in the'production of films and sheets it will be apparent that m new plasticizer may also be employed with advantage in the other branches of the plastic art. For instance, my above described composition of matter may be employed in the manufacture of artificial silk by the dry spinning method. With the proper coagulating bath it may also be employed for wet spinning; It may be desired to employ a composition of different viscosity or evaporation characteristics but this is a mere matter changing the solvent proportion or adding vaporation retardants such as triacetin or other high or intermediate boiling constituents, as has been well known in the art for more than a decade. My novel plasticizer may also be employed with advantage in connection with a number of the known lacquer and-varnish formulae with which it may be found to be compatible. In such cases the plasticizer is usually first put into solution with the cellulose derivative solution and if non-solvents are added for the purpose of cheapening the composition they are added only to such an extent as will not precipitate the derivative from solution. Other uses Within the scope of my invention will also suggest themselves to those skilled in the art.

What I claim as my invention, and desire to be secured by Letters Patent of the United States, is:

1. A composition of matter comprising a cellulose derivative and trimethylene glycol dibutyrate.

2. A composition of matter comprising cellulose acetate and trimethylene glycol dibutyrate. I

3. A composition of matter comprising 100 parts cellulose acetate and from about 10 to 30 parts, by Weight, of trimethylene glycol dibutyrate. v 0

4. A composition of matter comprising 100 parts of cellulose acetate and approximately 30 parts, by Weight, of trimethylene glycol dibutyrate.

Signed at Rochester, New York, this 27th day of August,--1929.

STEWART J. CARROLL. 

